Source: Duncan will not opt out

Tim Duncan is not expected to opt out of the final year of his contract, and the Spurs don’t plan to offer him an extension before the collective bargaining agreement expires Thursday, according to a source familiar with talks between the team and the franchise icon.

As such, Duncan will play out the final year of his existing deal, during which he is scheduled to earn $21.2 million, and remains on track to become a free agent after the 2011-12 campaign.

Duncan also faces a Thursday deadline to exercise an early-termination option. His apparent decision not to do so is not surprising in light of the league’s unsure labor climate.

With a contentious fight broiling between the NBA’s owners and players’ union this summer, and with so much uncertainty still surrounding the next CBA, Duncan has apparently determined it is in his best interest to stand pat on what, at age 35, is likely to be his last high-dollar payday.

Should Duncan choose to continue playing after next season, the Spurs would prefer to re-sign him under the new set of salary rules, which are generally expected to be more favorable to small-market clubs.

There had been some speculation Duncan might decide to trigger his early-termination option and renegotiate his contract, in a manner that might give the Spurs payroll flexibility to better fortify their roster next season.

Duncan took a similar approach in signing a four-year extension before the 2007-08 season, accepting less than maximum money and leaving the Spurs room to eventually add Richard Jefferson in the summer of 2009.

A 13-time All-Star, two-time league MVP and three-time Finals MVP, Duncan logged career lows last season in scoring (13.4 points per game), rebounding (8.9 per game) and minutes (28.4 per game).

Though more of a statistical bit player than he was in his prime, Duncan in his 14th NBA season remained the central figure for the Spurs, both on the court and in the locker room.

He’s not going to look like rookie Tim Duncan,” coach Gregg Popovich said in an interview conducted during the season. “Nobody is going to look like they did 14 years ago. He’s still so steady. He’s still our rock out there.”